A driving motor of vehicles generates driving power using a battery power. There are various types of motors such as, a motor for driving a water pump, a motor for driving an air blower, etc.
In general, a DC voltage is supplied as a driving voltage to an inverter for driving the motor. A voltage sensor is provided or a voltage sensing circuit is formed on a substrate to measure the DC voltage. When the voltage sensor (or the voltage sensing circuit) becomes defective, the DC voltage cannot be measured, thereby decreasing a motor control performance of the inverter.
FIGS. 9(a) and 9(b) are drawings in which a general sensor and a voltage sensor are compared.
As shown in FIGS. 9(a) and 9(b), when the general sensor (e.g., a pressure sensor) generates an output voltage range of 0 V to 5 V, only the voltage output range of 0.5 V to 4.5 V is used to determine disconnection or a short-circuit of the pressure sensor. That is, if 0 V or 5 V is outputted, the pressure sensor is determined to be disconnected or short-circuited.
However, in the case of the voltage sensor, even if the disconnection or short-circuit of the voltage sensor occur, the overall output voltage range of 0 V to 5 V should be used to sense the voltage, thereby failing to detect such faults.
Due to the disconnection or short-circuit of the voltage sensor, even if the driving voltage is supplied normally to the input terminal of the inverter, it can be determined that no driving voltage is supplied (i.e., output voltage=0 V) or the driving voltage exceeds the supplied voltage (i.e., output voltage=5 V)
That is, even if the driving voltage is supplied normally, output and dynamic characteristics of the motor deteriorate, and an operation of the motor should stop.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention, and therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.